A existing coupling device for two connecting poles often includes: a lower fixing sleeve sleeved on the upper portion of a lower connecting pole; a upper fixing sleeve sleeved on the lower portion of a upper connecting pole; the upper fixing sleeve can be sleeved into the lower fixing sleeve; screws and welding technology are often used to connect the upper fixing sleeve and the lower fixing sleeve. The upper connecting pole is slidably connected to the lower connecting pole. The disadvantages of the existing technology are as follow: firstly, it takes much time and labor to assemble the device; secondly, the connections are not secure; thirdly, the screws used to connect the upper fixing sleeve and the lower fixing sleeve are easy to break; fourthly, welding takes much time.
A need therefore exists for a coupling device for two connecting poles that eliminates the above described disadvantages and problems.